WO2017138905A1 - Scissors - Google Patents

Abstract

The scissors comprising two blades 1 with cutting edges 2 and terminating as handles 3, and an operating joint 4, which is used to pivot the blades and the handles about an axis 5 of rotation, the cutting edges of the blades being positioned between the axis of rotation and at least one pair of handles, in which the axis of rotation is positioned in front of the tips of the blades, while there are no other elements of the scissors between the axis of rotation and the blades. The technical result is that of ensuring no less pressing force at the tips of the blades than at the bases of their cutting edges, and a decrease of an angle between the cutting edges of the blades at their complete opening.

Description

SCISSORS

FIELD OF THE INVENTION

The present invention relates to handheld scissors (shears), for example, paper-cutting scissors, sewing, nail, and surgery scissors, metal-cutting shears, etc.

BACKGROUND OF THE INVENTION

Handheld scissors are well-known and comprise two interconnected blades with cutting edges and handles, and a pivotal connection (usually a hinge), the pivotal connection is used for pivoting the blades and the handles about an axis of rotation, while the blades themselves slide against each other (make a cutting movement) when the handles are closed. Hereinafter, the tips of the blades mean distal ends of the blades, or their front extremities. Hereinafter, the bases of the cutting edges mean the most remote from the tips of the blades parts of the cutting edges of the blades.

The prior art includes the scissors described in US, 1 ,359,762, which scissors have been open to the objection that under constant pressing force on the handles (rings) during their closing, the pressing force of the blades quickly decreases in the direction from the pivotal connection and the bases of the cutting edges of the blades toward their tips. That is why, in case of e.g. cutting relatively hard materials, in order to provide necessary pressing force of the blades under ordinary physical abilities of the user, it is needed to open the handles of the scissors as wide as possible what leads to undesired exertion of the hand, at the same time the length of a single cut can remain relatively short (substantially less than desired and possible one, based on the actual length of the cutting edges of the blades) for the mentioned above reasons. Another major drawback of the scissors is that at substantial opening of the blades, the angle between the cutting edges of the blades becomes sufficiently big to noticeably increase a possibility of undesired slipping out of an object positioned between the blades during closing of the latter. Hereinafter, the complete opening of the blades means such a position 7 000008

2 of the scissors at which the longest possible lengthwise gap between the cutting edges of the blades is formed - usually all the way from the tips of the blades to the bases of their cutting edges. And the complete closing of the blades means such a position of the scissors at which the tips of the blades are closest to each other. Any interim position of the scissors is therefore a partial opening of the blades.

Known in the art are scissors described in US, 303,486 D, which can be considered as an attempt to fix the aforementioned problems, while the scissors comprise two connected to handles (rings) blades with cutting edges, and a pivotal connection in the form of a hinge, the pivotal connection being used for pivoting the blades and handles about the axis of rotation, and the cutting edges of the blades of these scissors are positioned substantially between the axis of rotation and a pair of complementary handles (rings) positioned at the tips of the blades. This solution allows for essential increasing of pressing force at the tips of blades so addressing some of the problems of regular scissors. A drawback of this arrangement, apart from an unusual shape of the tips of the blades due to the complementary handles, is that operation of the scissors becomes awkward when the conventional handles are used, as the complementary handles complicate, for example, usual cutting of paper, and the blades can't have traditionally sharp tips, which are convenient when fulfilling some usual for scissors operations, for instance, when doing cuts inside a sheet of paper. Besides listed above drawbacks, when using these scissors, like in case of regular scissors, at substantially complete opening of its blades with purpose of positioning an object as close to the axis of rotation as possible (i.e. near the bases of the cutting edges of the blades) for increasing pressing force of the blades, an angle between the cutting edges of the blades becomes substantially big for essential increase of possibility of undesired slipping out of the object positioned between the blades when the latter are closed.

SUMMARY OF THE INVENTION It is an object of the invention to provide such hand scissors, which ensure no less pressing force at the tips of the blades than on the bases of their cutting 2017/000008

3 edges and a decrease of the angle between the blades at their substantially complete opening compared to the prior art with keeping a substantially convenient and habitual shape of the tips of the blades.

This object is achieved by providing the scissors comprising two blades with cutting edges and terminating as handles, and an operating joint, which is used to pivot the blades and the handles about an axis of rotation, the cutting edges of the blades being positioned substantially between the axis of rotation and at least one pair of handles, wherein according to the invention and with an object of providing pressing force at the tips of the blades no less than at the basis of their cutting edges and decreasing an angle between the cutting edges of the blades at their substantially complete opening, while providing a possibility of keeping substantially convenient and habitual shape of the tips of the blades, the axis of rotation is positioned substantially in front of the tips of the blades;

The scissors of the invention preferably have the operating joint comprised of at least two concentric slots provided on the blades, at least one slot on each of the blades, with a center substantially coinciding with the axis of rotation, and at least two sliders fixed on the blades, at least one slider on each blade, wherein at least one slider on each of the blades is movably positioned in the corresponding slot of the other blade;

The scissors preferably may have the radii of at least two slots substantially the same; and the radii of the slots can be so extensive that the slots can be considered substantially straight.

BRIEF DESCRIPTION OF THE DRAWINGS

This invention is described by drawings in which:

Fig. 1 is a general view of the scissors embodying this invention with the blades in partially open position;

Fig. 2 is an exploded view of the scissors embodying this invention;

Fig. 3 is a side view of the scissors embodying this invention in position of complete closing of the blades;

Fig. 4 is a side view of the scissors embodying this invention in position of complete opening of the blades. DETAILED DESCRIPTION OF THE INVENTION

The scissors according to this invention comprise two blades 1 (Fig. 1 ) with cutting edges 2, each of the blades 1 is connected, preferably as a single part, to a corresponding handle 3, which is preferably ring-shaped. Mutual movement (closing and opening) of the blades 1 is provided with the help of an operating joint 4 that supports rotation of the blades 1 and handles 3 about a common axis 5 of rotation that is positioned substantially in front of the tips of the blades 1 , while there are no other elements of the scissors between the axis 5 of rotation and the blades 1 , and the axis 5 of rotation preferably crosses with an imagined lengthwise line positioned in the middle between the blades 1 . The operating joint 4 is comprised of preferably two concentric slots 6 provided on the blades 1 , one slot 6 on each of the blades 1 , with a center coinciding with the axis 5 of rotation, and preferably two sliders 7 fixed on the blades 1 , one slider 7 on each of the blades 1 , meanwhile the slider 7 of each of the blades 1 is movably positioned in the corresponding slot 6 of the other blade 1 , and the width of the part of the slider 7 positioned inside the slot 6 is preferably close to the width of the corresponding slot 6. The radii of the slots 6 are preferably substantially same. Generally speaking, the radii of the slots 6 can be in a wide range of values, first of all, depending on a distance of the axis 5 of rotation from the tips of the blades 1. In particular, radii of the slots 6 can be so big, that the slots 6 can be considered substantially straight, in this case the pressing force of the blades 1 is substantially the same all the way along the length of the cutting edges 2. The sliders 7 (Fig. 2) are preferably attached to the corresponding blades 1 by the screws 8, it is preferable to use spring lock washers 9 for pressing the blades 1 to each other, for the same purpose the blades 1 can be bent towards each other, as it is done in the known scissors. Here it is necessary to note, that the tips of the blades 1 can have any appropriate shape depending on the primary application of the scissors (manicure, cutting paper, etc.), like in case of the known scissors. The blades 1 by itself and the cutting edges 2 can be of same shape as well as of different one depending on requirement of particular application and design. The axis 5 of rotation (Fig. 1 ) can substantially cross the lengthwise line in the middle between 17 000008

5 the blades 1 as well as be substantially afar from it (like in many known scissors). Quantity of the slots 6 (and suitably quantity of the sliders 7) can be two as well as more than two. While the operating joint 4, as described above, is positioned substantially between the cutting edges 2 of the blades 1 and the handles 3, the embodiments are possible where the handles 3 and the cutting edges 2 of the blades 1 are positioned at the same side of the operating joint 4.

The scissors according to this invention are operated similarly to regular scissors. When the scissors according to this invention are in position of complete closing of the blades 1 (Fig. 3), then to open the blades 1 it is enough to open the handles 3 and, correspondingly, the blades 1 at desired extent, up to position of complete opening of the blades 1 (Fig. 4) if needed, at that the sliders 7 move inside the concentric slots 6, thus entailing rotation of the blades 1 and the handles 3 about the axis 5 of rotation. As shown in Fig. 4, even in the position of the complete opening of the blades 1 the angle between the cutting edges 2 of the blades 1 remains relatively small if compared to the prior art. In process of cutting by the scissors according to this invention, the pressing force at the tips of the blades 1 is significantly more than at the bases of the cutting edges 2 as the axis 5 of rotation is located closer to the tips of the blades 1 , than to the bases of the cutting edges 2, as it clearly follows from the above description. This allows for more comfortable and precise cutting of dense materials like, e.g., cardboard, finger nails, etc. than in case of regular scissors.

Based on the above, the described scissors endure no less pressing force at the tips of the blades than on the bases of their cutting edges, and decrease of angle between the blades at their substantially complete opening compared to the prior art with convenient and habitual shape of the tips of the blades.

This invention is not limited to aforementioned embodiments and covers all other possible embodiments and modifications within the scope of its claims.

Claims

1. Scissors comprising two blades with cutting edges and terminating as handles, and an operating joint, which is used to pivot the blades and the handles about an axis of rotation, the cutting edges of the blades being positioned substantially between the axis of rotation and at least one pair of handles, characterized in that, with an object of providing pressing force at the tips of the blades no less than at the basis of their cutting edges and decreasing an angle between the cutting edges of the blades at their substantially complete opening, while providing a possibility of keeping substantially convenient and habitual shape of the tips of the blades, the axis of rotation is positioned substantially in front of the tips of the blades;

2. The scissors according to claim 1 , characterized in that the operating joint is comprised of at least two concentric slots provided on the blades, at least one slot on each of the blades, with a center substantially coinciding with the axis of rotation, and at least two sliders fixed on the blades, at least one slider on each blade, wherein at least one slider on each of the blades is movably positioned in the corresponding slot of the other blade;

3. The scissors according to claim 2, characterized in that the radii of at least two slots are substantially the same;

4. The scissors according to claim 2, characterized in that the radii of the slots are so extensive that the slots can be considered substantially straight.